Answer:
15 meters
Explanation:
The inicial energy of the ball is just potencial energy, and its value is:
E = m * g * h = m * g * 20,
where m is the ball mass, and g is the value of gravity.
In the moment that the ball strickes the ground, all potencial energy transformed into kinetic energy, and 25% of this energy is lost, so the total energy at this moment will be:
E' = 0.75 * E = 0.75 * m * g * 20 = 15*m*g
This kinetic energy will make the ball goes up again, and at the maximum height, all kinetic energy is transformed back into potencial energy.
So, as the mass and the gravity are constants, we can calculate the height the ball will reach:
E' = m*g*h = 15*m*g -> h = 15 meters
Answer:
the average speed of the swimmer is 0.069 m/s.
Explanation:
Given;
complete distance around the park pine, d = 25 m
total lap completed, = 20 laps
time of laps completion, t = 7200 s
The total distance completed by the swimmer = 20 x 25 = 500 m
The average speed of the swimmer = distance / time
= (500 m) / (7200 s)
= 0.069 m/s.
Therefore, the average speed of the swimmer is 0.069 m/s.
I think the answer would be T<span>ransverse, Longitudinal, & Surface waves.
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